Lecture 3 - Functional Neuroanatomy 2 Flashcards
What are Schwann cells?
myelination cells of the Peripheral Nervous System, can guide axon regeneration
Name 3 glial cells in the CNS.
Oligodendrocytes
Astrocytes
Microglia
What are Oligodendrocytes?
glial cells with extensions rich in myelin create myelin sheaths in the CNS
What are Astrocytes?
Large star shaped glial cells that provide structural integrity and create the “blood-brain” barrier. Recently been found to regulate breathing.
What are Microglia?
glial cells that respond to injury and disease (anti-inflamatory response), rapidly activate to stop pathogens and eliminates excess neurotransmitters
Multiple Sclerosis is…
Acute, inflammatory autoimmune disease. Breakdown of myelination and exposure of axons
Damage to the glial cells can show as…
Visual - blurred and double vision, nystagmus, ‘flashes’
Motor - weakness of muscles, slurred speech, muscle wastage, poor posture, tics
Sensory - numbness, tingling, pain
Coordination and balance
Cognitive - short- and long-term memory, forgetfulness, slowed recall
What are gliomas?
a malignant tumour of the Glial tissue of the nervous system
gliomas, astrocytomas and oligodendrogliomas
3 traits of a sensory neuron.
Afferent
Tends to be unipolar.
Attaches to the dorsal of the spine.
3 traits of a motor neuron.
Efferent
Tends to be multipolar
Attaches to the ventral of the spine.
What is a interneurone?
relay neuron in the centre of the spinal cord. passes information from a sensory neuron to a motor neuron.
What do dendrites do?
collect information from a connecting neuron
What, in a neuron, generate proteins?
Ribosomes
In a neuron, what is responsible for energy release?
Mitochondria
Describe Golgi Complex
Package proteins (ie. neurotransmitters) into vesicles for transport
What is contained within synaptic vesicles?
Neurotransmitters (proteins)
What are microtubules?
pathway used to transport neurotransmitters down the axon
What does myellin do?
protect the axon and promote transmission down the axon
What collects the neurotransmitters, in the vesicles, while they await release?
Terminal Buttons
Alzheimer’s diagnosis is associated with…
poor new learning
changed personality
language deficits
What does the external surface of the brain look like in an individual with Alzheimer’s Dementia?
Neuronal death, widening sulci and narrowed gyri mostly over the frontal and parietal lobes.
What are amyloid plaques?
Cellular trash
clumps of beta-amyloids, which destroy connections between nerve cells
What are two possible causes of dementia?
amyloid plaques and tangles
What are the 3 phases of neuronal communiction?
Collection and integration of signal
transmission of the signal along the axon
transmission of signal from the axon terminals
When a cell is at resting potential it is said to be…..
polarised
-70mV
What are the three parts of a synapse?
Presynaptic terminal
Junction/gap
Postsynaptic terminal
Axodendritic
axon terminal buttons on dendrites
Axosomatic
axon terminal buttons on soma/cell body
Dendritic spines
axon terminal buttons on spines of dendrites
Dendrodendritic
dendrite to dendrite, and often bidirectional transmission
Axoaxonic
can mediate presynaptic facilitation and inhibition of that button on the post synaptic neurone
What are the 2 most common types of synapses?
Axodendritic and Axosomatic
What are the small molecules called responsible for neurotransmission?
Neurotransmitters
What are the large molecules called responsible for neurotransmission?
Neuropeptides
4 examples of Neurotransmitters
Glutamate, GABA, Acetylcholine, norepinephrine
2 examples of Neuropeptides
Substance P, Endorphins
What are the 3 classes of neurotransmitters?
Amino acids
Monamines
Acetylcholine
Building blocks of protiens
Amino Acids
Synthesised from a single amino acid
monoamines
ACh
Acetylcholine
Most prevalent excitatory neurotransmitter
Glutamate
Most prevalent inhibitory neurotransmitter
GABA
Name 2 types of Monoamines
Catecholamines and indolamines
Examples of Catecholamines
dopamine
norepinephrine
epinephrine
Examples of Indolamines
Serotonin
Melatonin
What is the term for a substance which initiates a physiological response when combined with a receptor?
Agonist
What is the term for a substance which interferes with or inhibits the physiological action of another?
Antagonist
Function of Acetylcholine
It causes the contraction of skeletal muscles and activates glandular functions in the endocrine system
Release of a neurotransmitter
exocytosis
What are the 2 types of receptors on the post-synaptic membrane?
Ionotropic receptors and metabotropic receptors
Name a catecholamine agonist.
Cocaine
Blocks reuptake – preventing the activity of the neurotransmitter from being “turned off”
Name a GABA agonist
Benzodiazepines
Binds to the GABA molecule and increases thebinding of GABA
Name a ACh agonist
Physostigmine inhibits Acetylcholinestrase (Ache), which breaks down Ach
Name 2 ACh antagonists
Atrpopine
Binds and blocks muscarinic receptors
Many of these metabotropic receptors are in the brain
High doses disrupt memory
Curare
Bind and blocks nicotinic receptors, the ionotropic receptors at the neuromuscular junction
Causes paralysis
Treated with physostigmine
Agonist drug that increase synthesis of dopamine
L-dopa
Agonist drug the increases the release of ACh
Black widow spider venom
Agonist drug that stimulates ACh receptors
Nicotine
Agonist drugs that block the reuptake of dopamine
Amphetamines, cocaine, methyphenidate
Antagonist drug inhibits the synthesis of serotonin
PCPA
Antagonist drug that prevents storage of monoamines in vesicles
Reserpine
Antagonist drug that blocks release of ACh
Botulinum toxin (BoTox)
Antagonist drug that stimulates dopamines autoreceptors and inhibits the release of dopamine
Apomorphine
Antagonist drug that blocks postsynaptic ACh receptors
Curare
Disorder which destroys Ach
Myathenia Gravis
